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Giri RK. Molecular signatures in prion disease: altered death receptor pathways in a mouse model. J Transl Med 2024; 22:503. [PMID: 38802941 PMCID: PMC11129387 DOI: 10.1186/s12967-024-05121-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Accepted: 03/20/2024] [Indexed: 05/29/2024] Open
Abstract
BACKGROUND Prion diseases are transmissible and fatal neurodegenerative diseases characterized by accumulation of misfolded prion protein isoform (PrPSc), astrocytosis, microgliosis, spongiosis, and neurodegeneration. Elevated levels of cell membrane associated PrPSc protein and inflammatory cytokines hint towards the activation of death receptor (DR) pathway/s in prion diseases. Activation of DRs regulate, either cell survival or apoptosis, autophagy and necroptosis based on the adaptors they interact. Very little is known about the DR pathways activation in prion disease. DR3 and DR5 that are expressed in normal mouse brain were never studied in prion disease, so also their ligands and any DR adaptors. This research gap is notable and investigated in the present study. METHODS C57BL/6J mice were infected with Rocky Mountain Laboratory scrapie mouse prion strain. The progression of prion disease was examined by observing morphological and behavioural abnormalities. The levels of PrP isoforms and GFAP were measured as the marker of PrPSc accumulation and astrocytosis respectively using antibody-based techniques that detect proteins on blot and brain section. The levels of DRs, their glycosylation and ectodomain shedding, and associated factors warrant their examination at protein level, hence western blot analysis was employed in this study. RESULTS Prion-infected mice developed motor deficits and neuropathology like PrPSc accumulation and astrocytosis similar to other prion diseases. Results from this research show higher expression of all DR ligands, TNFR1, Fas and p75NTR but decreased levels DR3 and DR5. The levels of DR adaptor proteins like TRADD and TRAF2 (primarily regulate pro-survival pathways) are reduced. FADD, which primarily regulate cell death, its level remains unchanged. RIPK1, which regulate pro-survival, apoptosis and necroptosis, its expression and proteolysis (inhibits necroptosis but activates apoptosis) are increased. CONCLUSIONS The findings from the present study provide evidence towards the involvement of DR3, DR5, DR6, TL1A, TRAIL, TRADD, TRAF2, FADD and RIPK1 for the first time in prion diseases. The knowledge obtained from this research discuss the possible impacts of these 16 differentially expressed DR factors on our understanding towards the multifaceted neuropathology of prion diseases and towards future explorations into potential targeted therapeutic interventions for prion disease specific neuropathology.
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Affiliation(s)
- Ranjit Kumar Giri
- Molecular and Cellular Neuroscience Division, National Brain Research Centre, Manesar, Gurgaon, Haryana, 122052, India.
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The Therapeutic Prospects of Targeting IL-1R1 for the Modulation of Neuroinflammation in Central Nervous System Disorders. Int J Mol Sci 2022; 23:ijms23031731. [PMID: 35163653 PMCID: PMC8915186 DOI: 10.3390/ijms23031731] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/24/2022] [Accepted: 01/30/2022] [Indexed: 11/16/2022] Open
Abstract
The interleukin-1 receptor type 1 (IL-1R1) holds pivotal roles in the immune system, as it is positioned at the “epicenter” of the inflammatory signaling networks. Increased levels of the cytokine IL-1 are a recognized feature of the immune response in the central nervous system (CNS) during injury and disease, i.e., neuroinflammation. Despite IL-1/IL-1R1 signaling within the CNS having been the subject of several studies, the roles of IL-1R1 in the CNS cellular milieu still cause controversy. Without much doubt, however, the persistent activation of the IL-1/IL-1R1 signaling pathway is intimately linked with the pathogenesis of a plethora of CNS disease states, ranging from Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS), all the way to schizophrenia and prion diseases. Importantly, a growing body of evidence is showing that blocking IL-1R1 signaling via pharmacological or genetic means in different experimental models of said CNS diseases leads to reduced neuroinflammation and delayed disease progression. The aim of this paper is to review the recent progress in the study of the biological roles of IL-1R1, as well as to highlight key aspects that render IL-1R1 a promising target for the development of novel disease-modifying treatments for multiple CNS indications.
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Neuroimmune Response Mediated by Cytokines in Natural Scrapie after Chronic Dexamethasone Treatment. Biomolecules 2021; 11:biom11020204. [PMID: 33540568 PMCID: PMC7912810 DOI: 10.3390/biom11020204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 01/27/2021] [Indexed: 01/15/2023] Open
Abstract
The actual role of prion protein-induced glial activation and subsequent cytokine secretion during prion diseases is still incompletely understood. The overall aim of this study is to assess the effect of an anti-inflammatory treatment with dexamethasone on different cytokines released by neuroglial cells that are potentially related to neuroinflammation in natural scrapie. This study emphasizes the complex interactions existent among several pleiotropic neuromodulator peptides and provides a global approach to clarify neuroinflammatory processes in prion diseases. Additionally, an impairment of communication between microglial and astroglial populations mediated by cytokines, mainly IL-1, is suggested. The main novelty of this study is that it is the first one assessing in situ neuroinflammatory activity in relation to chronic anti-inflammatory therapy, gaining relevance because it is based on a natural model. The cytokine profile data would suggest the activation of some neurotoxicity-associated route. Consequently, targeting such a pathway might be a new approach to modify the damaging effects of neuroinflammation.
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Microglia in Prion Diseases: Angels or Demons? Int J Mol Sci 2020; 21:ijms21207765. [PMID: 33092220 PMCID: PMC7589037 DOI: 10.3390/ijms21207765] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/16/2020] [Accepted: 10/16/2020] [Indexed: 02/08/2023] Open
Abstract
Prion diseases are rare transmissible neurodegenerative disorders caused by the accumulation of a misfolded isoform (PrPSc) of the cellular prion protein (PrPC) in the central nervous system (CNS). Neuropathological hallmarks of prion diseases are neuronal loss, astrogliosis, and enhanced microglial proliferation and activation. As immune cells of the CNS, microglia participate both in the maintenance of the normal brain physiology and in driving the neuroinflammatory response to acute or chronic (e.g., neurodegenerative disorders) insults. Microglia involvement in prion diseases, however, is far from being clearly understood. During this review, we summarize and discuss controversial findings, both in patient and animal models, suggesting a neuroprotective role of microglia in prion disease pathogenesis and progression, or—conversely—a microglia-mediated exacerbation of neurotoxicity in later stages of disease. We also will consider the active participation of PrPC in microglial functions, by discussing previous reports, but also by presenting unpublished results that support a role for PrPC in cytokine secretion by activated primary microglia.
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Chen J, Chen C, Hu C, Liu L, Xia Y, Wang L, Yang W, Wu HY, Zhou W, Xiao K, Shi Q, Wu Y, Chen ZB, Dong XP. IP10, KC and M-CSF Are Remarkably Increased in the Brains from the Various Strains of Experimental Mice Infected with Different Scrapie Agents. Virol Sin 2020; 35:614-625. [PMID: 32314275 PMCID: PMC7736440 DOI: 10.1007/s12250-020-00216-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 11/27/2019] [Indexed: 12/21/2022] Open
Abstract
Activation of inflammatory cells and upregulations of a number of cytokines in the central nervous system (CNS) of patients with prion diseases are frequently observed. To evaluate the potential changes of some brain cytokines that were rarely addressed during prion infection, the levels of 17 different cytokines in the brain homogenates of mice infected with different scrapie mouse-adapted agents were firstly screened with Luminex assay. Significant upregulations of interferon gamma-induced protein 10 (IP10), keratinocyte chemoattractant (KC) and macrophage colony stimulating factor (M-CSF) were frequently detected in the brain lysates of many strains of scrapie infected mice. The upregulations of those three cytokines in the brains of scrapie infected mice were further validated by the individual specific ELISA and immunohistochemical assay. Increased specific mRNAs of IP10, M-CSF and KC in the brains of scrapie infected mice were also detected by the individual specific qRT-PCRs and IP10-specific digital PCR. Dynamic analyses of the brain samples collected at different time points post infection revealed the time-dependent increases of those three cytokines, particularly IP10 during the incubation period of scrapie infection. In addition, we also found that the levels of IP10 in cerebral spinal fluid (CSF) of 45 sporadic Creutzfeldt-Jakob disease (sCJD) patients were slightly but significantly higher than those of the cases who were excluded the diagnosis of prion diseases. These data give us a better understanding of inflammatory reaction during prion infection and progression of prion disease.
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Affiliation(s)
- Jia Chen
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163000, China
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China
| | - Cao Chen
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China.
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310000, China.
- Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430000, China.
| | - Chao Hu
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310000, China
| | - Lian Liu
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Daqing, 163000, China
| | - Ying Xia
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Daqing, 163000, China
| | - Lin Wang
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Daqing, 163000, China
| | - Wei Yang
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Daqing, 163000, China
| | - Hai-Yan Wu
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163000, China
| | - Wei Zhou
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310000, China
| | - Kang Xiao
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310000, China
| | - Qi Shi
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310000, China
| | - Yuezhang Wu
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China
| | - Zhi-Bao Chen
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163000, China.
| | - Xiao-Ping Dong
- State Key Laboratory of Infectious Disease Prevention and Control, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, 100000, China.
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, 310000, China.
- Center for Global Public Health, Chinese Center for Disease Control and Prevention, Beijing, 100000, China.
- Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430000, China.
- China Academy of Chinese Medical Sciences, Beijing, 100000, China.
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6
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Guijarro IM, Garcés M, Marín B, Otero A, Barrio T, Badiola JJ, Monzón M. Neuroimmune Response in Natural Preclinical Scrapie after Dexamethasone Treatment. Int J Mol Sci 2020; 21:ijms21165779. [PMID: 32806582 PMCID: PMC7460817 DOI: 10.3390/ijms21165779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 08/04/2020] [Accepted: 08/10/2020] [Indexed: 12/18/2022] Open
Abstract
A recently published report on chronic dexamethasone treatment for natural scrapie supported the hypothesis of the potential failure of astroglia in the advanced stage of disease. Herein, we aimed to extend the aforementioned study on the effect of this anti-inflammatory therapy to the initial phase of scrapie, with the aim of elucidating the natural neuroinflammatory process occurring in this neurodegenerative disorder. The administration of this glucocorticoid resulted in an outstanding reduction in vacuolation and aberrant protein deposition (nearly null), and an increase in glial activation. Furthermore, evident suppression of IL-1R and IL-6 and the exacerbation of IL-1α, IL-2R, IL-10R and IFNγR were also demonstrated. Consequently, the early stage of the disease is characterized by an intact neuroglial response similar to that of healthy individuals attempting to re-establish homeostasis. A complex network of neuroinflammatory markers is involved from the very early stages of this prion disease, which probably becomes impaired in the more advanced stages. The in vivo animal model used herein provides essential observations on the pathogenesis of natural scrapie, as well as the possibility of establishing neuroglia as potential target cells for anti-inflammatory therapy.
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Fragkoudis R, Dixon-Ballany CM, Zagrajek AK, Kedzierski L, Fazakerley JK. Following Acute Encephalitis, Semliki Forest Virus is Undetectable in the Brain by Infectivity Assays but Functional Virus RNA Capable of Generating Infectious Virus Persists for Life. Viruses 2018; 10:v10050273. [PMID: 29783708 PMCID: PMC5977266 DOI: 10.3390/v10050273] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/14/2018] [Accepted: 05/17/2018] [Indexed: 12/24/2022] Open
Abstract
Alphaviruses are mosquito-transmitted RNA viruses which generally cause acute disease including mild febrile illness, rash, arthralgia, myalgia and more severely, encephalitis. In the mouse, peripheral infection with Semliki Forest virus (SFV) results in encephalitis. With non-virulent strains, infectious virus is detectable in the brain, by standard infectivity assays, for around ten days. As we have shown previously, in severe combined immunodeficient (SCID) mice, infectious virus is detectable for months in the brain. Here we show that in MHC-II-/- mice, with no functional CD4 T-cells, infectious virus is also detectable in the brain for long periods. In contrast, in the brains of CD8-/- mice, virus RNA persists but infectious virus is not detectable. In SCID mice infected with SFV, repeated intraperitoneal administration of anti-SFV immune serum rapidly reduced the titer of infectious virus in the brain to undetectable, however virus RNA persisted. Repeated intraperitoneal passive transfer of immune serum resulted in maintenance of brain virus RNA, with no detectable infectious virus, for several weeks. When passive antibody transfer was stopped, antibody levels declined and infectious virus was again detectable in the brain. In aged immunocompetent mice, previously infected with SFV, immunosuppression of antibody responses many months after initial infection also resulted in renewed ability to detect infectious virus in the brain. In summary, antiviral antibodies control and determine whether infectious virus is detectable in the brain but immune responses cannot clear this infection from the brain. Functional virus RNA capable of generating infectious virus persists and if antibody levels decline, infectious virus is again detectable.
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MESH Headings
- Animals
- Antibodies, Viral/blood
- Antibodies, Viral/immunology
- Antibodies, Viral/therapeutic use
- Brain/immunology
- Brain/virology
- Cell Line
- Cricetinae
- Cyclophosphamide/pharmacology
- Encephalitis, Viral/immunology
- Encephalitis, Viral/virology
- Immune Sera/immunology
- Immune Sera/isolation & purification
- Immunity, Cellular/drug effects
- Immunosuppressive Agents/pharmacology
- Mice
- Mice, Inbred Strains
- Mice, SCID
- RNA, Viral/genetics
- RNA, Viral/immunology
- Semliki forest virus/growth & development
- Semliki forest virus/immunology
- Semliki forest virus/physiology
- T-Lymphocytes/immunology
- Viral Plaque Assay
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Affiliation(s)
- Rennos Fragkoudis
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, College of Medicine & Veterinary Medicine, University of Edinburgh, Edinburgh, Midlothian EH25 9RG, UK.
- The School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington Campus, Leicestershire LE12 5RD, UK.
| | - Catherine M Dixon-Ballany
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, College of Medicine & Veterinary Medicine, University of Edinburgh, Edinburgh, Midlothian EH25 9RG, UK.
| | - Adrian K Zagrajek
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, College of Medicine & Veterinary Medicine, University of Edinburgh, Edinburgh, Midlothian EH25 9RG, UK.
| | - Lukasz Kedzierski
- Department of Microbiology and Immunology, Faculty of Medicine, Dentistry and Health Sciences at The Peter Doherty Institute for Infection and Immunity and the Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, 792 Elizabeth Street, Melbourne 3000, Australia.
| | - John K Fazakerley
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, College of Medicine & Veterinary Medicine, University of Edinburgh, Edinburgh, Midlothian EH25 9RG, UK.
- Department of Microbiology and Immunology, Faculty of Medicine, Dentistry and Health Sciences at The Peter Doherty Institute for Infection and Immunity and the Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, 792 Elizabeth Street, Melbourne 3000, Australia.
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Nuvolone M, Sorce S, Schwarz P, Aguzzi A. Prion pathogenesis in the absence of NLRP3/ASC inflammasomes. PLoS One 2015; 10:e0117208. [PMID: 25671600 PMCID: PMC4324825 DOI: 10.1371/journal.pone.0117208] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 12/19/2014] [Indexed: 12/31/2022] Open
Abstract
The accumulation of the scrapie prion protein PrPSc, a misfolded conformer of the cellular prion protein PrPC, is a crucial feature of prion diseases. In the central nervous system, this process is accompanied by conspicuous microglia activation. The NLRP3 inflammasome is a multi-molecular complex which can sense heterogeneous pathogen-associated molecular patterns and culminates in the activation of caspase 1 and release of IL 1β. The NLRP3 inflammasome was reported to be essential for IL 1β release after in vitro exposure to the amyloidogenic peptide PrP106-126 and to recombinant PrP fibrils. We therefore studied the role of the NLRP3 inflammasome in a mouse model of prion infection. Upon intracerebral inoculation with scrapie prions (strain RML), mice lacking NLRP3 (Nlrp3-/-) or the inflammasome adaptor protein ASC (Pycard-/-) succumbed to scrapie with attack rates and incubation times similar to wild-type mice, and developed the classic histologic and biochemical features of prion diseases. Genetic ablation of NLRP3 or ASC did not significantly impact on brain levels of IL 1β at the terminal stage of disease. Our results exclude a significant role for NLRP3 and ASC in prion pathogenesis and invalidate their claimed potential as therapeutic target against prion diseases.
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Affiliation(s)
- Mario Nuvolone
- Institute of Neuropathology, University Hospital of Zurich, Zurich, Switzerland
- * E-mail: (AA); (MN)
| | - Silvia Sorce
- Institute of Neuropathology, University Hospital of Zurich, Zurich, Switzerland
| | - Petra Schwarz
- Institute of Neuropathology, University Hospital of Zurich, Zurich, Switzerland
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital of Zurich, Zurich, Switzerland
- * E-mail: (AA); (MN)
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Prion infection of mouse brain reveals multiple new upregulated genes involved in neuroinflammation or signal transduction. J Virol 2014; 89:2388-404. [PMID: 25505076 DOI: 10.1128/jvi.02952-14] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
UNLABELLED Gliosis is often a preclinical pathological finding in neurodegenerative diseases, including prion diseases, but the mechanisms facilitating gliosis and neuronal damage in these diseases are not understood. To expand our knowledge of the neuroinflammatory response in prion diseases, we assessed the expression of key genes and proteins involved in the inflammatory response and signal transduction in mouse brain at various times after scrapie infection. In brains of scrapie-infected mice at pre- and postclinical stages, we identified 15 previously unreported differentially expressed genes related to inflammation or activation of the STAT signal transduction pathway. Levels for the majority of differentially expressed genes increased with time postinfection. In quantitative immunoblotting experiments of STAT proteins, STAT1α, phosphorylated-STAT1α (pSTAT1α), and pSTAT3 were increased between 94 and 131 days postinfection (p.i.) in brains of mice infected with strain 22L. Furthermore, a select group of STAT-associated genes was increased preclinically during scrapie infection, suggesting early activation of the STAT signal transduction pathway. Comparison of inflammatory markers between mice infected with scrapie strains 22L and RML indicated that the inflammatory responses and gene expression profiles in the brains were strikingly similar, even though these scrapie strains infect different brain regions. The endogenous interleukin-1 receptor antagonist (IL-1Ra), an inflammatory marker, was newly identified as increasing preclinically in our model and therefore might influence scrapie pathogenesis in vivo. However, in IL-1Ra-deficient or overexpressor transgenic mice inoculated with scrapie, neither loss nor overexpression of IL-1Ra demonstrated any observable effect on gliosis, protease-resistant prion protein (PrPres) formation, disease tempo, pathology, or expression of the inflammatory genes analyzed. IMPORTANCE Prion infection leads to PrPres deposition, gliosis, and neuroinflammation in the central nervous system before signs of clinical illness. Using a scrapie mouse model of prion disease to assess various time points postinoculation, we identified 15 unreported genes that were increased in the brains of scrapie-infected mice and were associated with inflammation and/or JAK-STAT activation. Comparison of mice infected with two scrapie strains (22L and RML), which have dissimilar neuropathologies, indicated that the inflammatory responses and gene expression profiles in the brains were similar. Genes that increased prior to clinical signs might be involved in controlling scrapie infection or in facilitating damage to host tissues. We tested the possible role of the endogenous IL-1Ra, which was increased at 70 days p.i. In scrapie-infected mice deficient in or overexpressing IL-1Ra, there was no observable effect on gliosis, PrPres formation, disease tempo, pathology, or expression of inflammatory genes analyzed.
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10
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Llorens F, López-González I, Thüne K, Carmona M, Zafar S, Andréoletti O, Zerr I, Ferrer I. Subtype and regional-specific neuroinflammation in sporadic creutzfeldt-jakob disease. Front Aging Neurosci 2014; 6:198. [PMID: 25136317 PMCID: PMC4120692 DOI: 10.3389/fnagi.2014.00198] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Accepted: 07/19/2014] [Indexed: 11/13/2022] Open
Abstract
The present study identifies deregulated cytokines and mediators of the immune response in the frontal cortex and cerebellum of sporadic Creutzfeldt-Jakob disease (sCJD) MM1 and VV2 subtypes compared to age-matched controls. Deregulated genes include pro- and anti-inflammatory cytokines, toll-like receptors, colony stimulating factors, cathepsins, members of the complement system, and members of the integrin and CTL/CTLD family with particular regional and sCJD subtype patterns. Analysis of cytokines and mediators at protein level shows expression of selected molecules and receptors in neurons, in astrocytes, and/or in microglia, thus suggesting interactions between neurons and glial cells, mainly microglia, in the neuroinflammatory response in sCJD. Similar inflammatory responses have been shown in the tg340 sCJD MM1 mice, revealing a progressive deregulation of inflammatory mediators with disease progression. Yet, inflammatory molecules involved are subjected to species differences in humans and mice. Moreover, inflammatory-related cell signaling pathways NFκB/IKK and JAK/STAT are activated in sCJD and sCJD MM1 mice. Together, the present observations show a self-sustained complex inflammatory and inflammatory-related responses occurring already at early clinical stages in animal model and dramatically progressing at advanced stages of sCJD. Considering this scenario, measures tailored to modulate (activate or inhibit) specific molecules could be therapeutic options in CJD.
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Affiliation(s)
- Franc Llorens
- Department of Neurology, Clinical Dementia Center and DZNE, University Medical School, Georg-August University , Göttingen , Germany ; Institute of Neuropathology, IDIBELL-University Hospital Bellvitge, University of Barcelona, Hospitalet de Llobregat , Barcelona , Spain
| | - Irene López-González
- Institute of Neuropathology, IDIBELL-University Hospital Bellvitge, University of Barcelona, Hospitalet de Llobregat , Barcelona , Spain
| | - Katrin Thüne
- Department of Neurology, Clinical Dementia Center and DZNE, University Medical School, Georg-August University , Göttingen , Germany
| | - Margarita Carmona
- Institute of Neuropathology, IDIBELL-University Hospital Bellvitge, University of Barcelona, Hospitalet de Llobregat , Barcelona , Spain ; Network Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute Carlos III, Ministry of Health , Madrid , Spain
| | - Saima Zafar
- Department of Neurology, Clinical Dementia Center and DZNE, University Medical School, Georg-August University , Göttingen , Germany
| | - Olivier Andréoletti
- Ecole Nationale Vétérinaire de Toulouse, Institut National de la Recherche Agronomique , Toulouse , France
| | - Inga Zerr
- Department of Neurology, Clinical Dementia Center and DZNE, University Medical School, Georg-August University , Göttingen , Germany
| | - Isidre Ferrer
- Institute of Neuropathology, IDIBELL-University Hospital Bellvitge, University of Barcelona, Hospitalet de Llobregat , Barcelona , Spain ; Network Center for Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute Carlos III, Ministry of Health , Madrid , Spain
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11
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Gruden MA, Yanamandra K, Kucheryanu VG, Bocharova OR, Sherstnev VV, Morozova-Roche LA, Sewell RDE. Correlation between protective immunity to α-synuclein aggregates, oxidative stress and inflammation. Neuroimmunomodulation 2012; 19:334-342. [PMID: 22986484 DOI: 10.1159/000341400] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 06/15/2012] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE Protein aggregation leading to central amyloid deposition is implicated in Parkinson's disease (PD). During disease progression, inflammation and oxidative stress may well invoke humoral immunity against pathological aggregates of PD-associated α-synuclein. The aim was to investigate any possible concurrence between autoimmune responses to α-synuclein monomers, oligomers or fibrils with oxidative stress and inflammation. METHODS The formation of α-synuclein amyloid species was assessed by thioflavin-T assay and atomic force microscopy was employed to confirm their morphology. Serum autoantibody titers to α-synuclein conformations were determined by ELISA. Enzyme activity and concentrations of oxidative stress/inflammatory indicators were evaluated by enzyme and ELISA protocols. RESULTS In PD patient sera, a differential increase in autoantibody titers to α-synuclein monomers, toxic oligomers or fibrils was associated with boosted levels of the pro-inflammatory cytokine interleukin-6 and tumour necrosis factor-α, but a decrease in interferon-γ concentration. In addition, levels of malondialdehyde were elevated whilst those of glutathione were reduced along with decrements in the activity of the antioxidants: superoxide dismutase, catalase and glutathione transferase. CONCLUSIONS It is hypothesized that the generation of α-synuclein amyloid aggregates allied with oxidative stress and inflammatory reactions may invoke humoral immunity protecting against dopaminergic neuronal death. Hence, humoral immunity is a common integrative factor throughout PD progression which is directed towards prevention of further neurodegeneration, so potential treatment strategies should attempt to maintain PD patient immune status.
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Early cytokine elevation, PrPres deposition, and gliosis in mouse scrapie: no effect on disease by deletion of cytokine genes IL-12p40 and IL-12p35. J Virol 2012; 86:10377-83. [PMID: 22787236 DOI: 10.1128/jvi.01340-12] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Neurodegenerative diseases are typically associated with an activation of glia and an increased level of cytokines. In our previous studies of prion disease, the cytokine response in the brains of clinically sick scrapie-infected mice was restricted to a small group of cytokines, of which IL-12p40, CCL2, and CXCL10 were present at the highest levels. The goal of our current research was to determine the relationship between cytokine responses, gliosis, and neuropathology during prion disease. Here, in time course studies of C57BL/10 mice intracerebrally inoculated with 22L scrapie, abnormal protease-resistant prion protein (PrPres), astrogliosis, and microgliosis were first detected at 40 days after intracerebral scrapie inoculation. In cytokine studies, IL-12p40 was first elevated by 60 days; CCL3, IL-1β, and CXCL1 were elevated by 80 days; and CCL2 and CCL5 were elevated by 115 days. IL-12p40 showed the most extensive increase throughout disease and was 30-fold above control levels at the terminal stage. Because of the early onset and dramatic elevation of IL-12p40 during scrapie, we investigated whether IL-12p40 contributed to the development of prion disease neuropathogenesis by using three different scrapie strains (22L, RML, 79A) to infect knockout mice in which the gene encoding IL-12p40 was deleted. We also studied knockout mice lacking IL-12p35, which combines with IL-12p40 to form active IL-12 heterodimers. In all instances, knockout mice did not differ from control mice in survival time, clinical tempo, or levels of spongiosis, gliosis, or PrPres in the brain. Thus, neither IL-12p40 nor IL-12p35 molecules were required for prion disease-associated neurodegeneration or neuroinflammation.
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Iwamaru Y, Takenouchi T, Murayama Y, Okada H, Imamura M, Shimizu Y, Hashimoto M, Mohri S, Yokoyama T, Kitani H. Anti-prion activity of Brilliant Blue G. PLoS One 2012; 7:e37896. [PMID: 22693582 PMCID: PMC3365075 DOI: 10.1371/journal.pone.0037896] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 04/30/2012] [Indexed: 12/11/2022] Open
Abstract
Background Prion diseases are fatal neurodegenerative disorders with no effective therapy currently available. Accumulating evidence has implicated over-activation of P2X7 ionotropic purinergic receptor (P2X7R) in the progression of neuronal loss in several neurodegenerative diseases. This has led to the speculation that simultaneous blockade of this receptor and prion replication can be an effective therapeutic strategy for prion diseases. We have focused on Brilliant Blue G (BBG), a well-known P2X7R antagonist, possessing a chemical structure expected to confer anti-prion activity and examined its inhibitory effect on the accumulation of pathogenic isoforms of prion protein (PrPres) in a cellular and a mouse model of prion disease in order to determine its therapeutic potential. Principal Findings BBG prevented PrPres accumulation in infected MG20 microglial and N2a neural cells at 50% inhibitory concentrations of 14.6 and 3.2 µM, respectively. Administration of BBG in vivo also reduced PrPres accumulation in the brains of mice with prion disease. However, it did not appear to alleviate the disease progression compared to the vehicle-treated controls, implying a complex role of P2X7R on the neuronal degeneration in prion diseases. Significance These results provide novel insights into the pathophysiology of prion diseases and have important implications for the treatment.
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Affiliation(s)
- Yoshifumi Iwamaru
- Prion Disease Research Center, National Institute of Animal Health, Tsukuba, Ibaraki, Japan
| | - Takato Takenouchi
- Animal Immune and Cell Biology Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan
| | - Yuichi Murayama
- Prion Disease Research Center, National Institute of Animal Health, Tsukuba, Ibaraki, Japan
| | - Hiroyuki Okada
- Prion Disease Research Center, National Institute of Animal Health, Tsukuba, Ibaraki, Japan
| | - Morikazu Imamura
- Prion Disease Research Center, National Institute of Animal Health, Tsukuba, Ibaraki, Japan
| | - Yoshihisa Shimizu
- Prion Disease Research Center, National Institute of Animal Health, Tsukuba, Ibaraki, Japan
| | - Makoto Hashimoto
- Division of Sensory and Motor Systems, Tokyo Metropolitan Institute of Medical Science, Setagaya-ku, Tokyo, Japan
| | - Shirou Mohri
- Prion Disease Research Center, National Institute of Animal Health, Tsukuba, Ibaraki, Japan
| | - Takashi Yokoyama
- Prion Disease Research Center, National Institute of Animal Health, Tsukuba, Ibaraki, Japan
| | - Hiroshi Kitani
- Animal Immune and Cell Biology Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan
- * E-mail:
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Tribouillard-Tanvier D, Carroll JA, Moore RA, Striebel JF, Chesebro B. Role of cyclophilin A from brains of prion-infected mice in stimulation of cytokine release by microglia and astroglia in vitro. J Biol Chem 2011; 287:4628-39. [PMID: 22179611 DOI: 10.1074/jbc.m111.269480] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Prion diseases or transmissible spongiform encephalopathy diseases are typically characterized by deposition of abnormally folded partially protease-resistant host-derived prion protein (PrPres), which is associated with activated glia and increased release of cytokines. This neuroinflammatory response may play a role in transmissible spongiform encephalopathy pathogenesis. We previously reported that brain homogenates from prion-infected mice induced cytokine protein release in primary astroglial and microglial cell cultures. Here we measured cytokine release by cultured glial cells to determine what factors in infected brain contributed to activation of microglia and astroglia. In assays analyzing IL-12p40 and CCL2 (MCP-1), glial cells were not stimulated in vitro by either PrPres purified from infected mouse brains or prion protein amyloid fibrils produced in vitro. However, significant glial stimulation was induced by clarified scrapie brain homogenates lacking PrPres. This stimulation was greatly reduced both by antibody to cyclophilin A (CyPA), a known mediator of inflammation in peripheral tissues, and by cyclosporine A, a CyPA inhibitor. In biochemical studies, purified truncated CyPA fragments stimulated a pattern of cytokine release by microglia and astroglia similar to that induced by scrapie-infected brain homogenates, whereas purified full-length CyPA was a poor stimulator. This requirement for CyPA truncation was not reported in previous studies of stimulation of peripheral macrophages, endothelial cell cardiomyocytes, and vascular smooth muscle cells. Therefore, truncated CyPA detected in brain following prion infection may have an important role in the activation of brain-derived primary astroglia and microglia in prion disease and perhaps other neurodegenerative or neuroinflammatory diseases.
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Affiliation(s)
- Déborah Tribouillard-Tanvier
- From the Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, NIAID, National Institutes of Health, Hamilton, Montana 59840
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Newsom DM, Liggitt HD, O’Rourke K, Zhuang D, Schneider DA, Harrington RD. Cytokine antibody array analysis in brain and periphery of scrapie-infected Tg338 mice. Comp Immunol Microbiol Infect Dis 2011; 34:387-97. [DOI: 10.1016/j.cimid.2011.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 06/21/2011] [Accepted: 06/28/2011] [Indexed: 11/25/2022]
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Hughes MM, Field RH, Perry VH, Murray CL, Cunningham C. Microglia in the degenerating brain are capable of phagocytosis of beads and of apoptotic cells, but do not efficiently remove PrPSc, even upon LPS stimulation. Glia 2011; 58:2017-30. [PMID: 20878768 PMCID: PMC3498730 DOI: 10.1002/glia.21070] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Despite the phagocytic machinery available to microglia the aberrant amyloid proteins produced during Alzheimer's and prion disease, amyloid-β and PrP(Sc), are inefficiently cleared. We have shown that microglia in the ME7 model of prion disease show morphological evidence of activation, synthesize low levels of pro-inflammatory cytokines and are primed to produce exaggerated responses to subsequent inflammatory challenges. Whether these microglia engage in significant phagocytic activity in the disease per se, or upon subsequent inflammatory challenge is not clear. In the present study we show transcriptional activation of a large number of scavenger receptors (SRs), matrix metalloproteinases (MMPs), oxidative enzymes, and cathepsins in ME7 animals. Hippocampally-injected inert latex beads (6 μm) are efficiently phagocytosed by microglia of ME7 prion-diseased animals, but not by microglia in normal animals. Stimulation of ME7 animals with systemic bacterial endotoxin (lipopolysaccharide, LPS) induced further increases in SR-A2, MMP3, and urokinase plasminogen activator receptor (uPAR) but decreased, or did not alter, transcription of most phagocytosis-related genes examined and did not enhance clearance of deposited PrP(Sc). Furthermore, intracerebral injection with LPS (0.5 μg) induced marked microglial production of IL-1β, robust cellular infiltration and marked apoptosis but also did not induce further clearance of PrP(Sc). These data indicate that microglia in the prion-diseased brain are capable of phagocytosis per se, but show limited efficacy in removing PrP(Sc) even upon marked escalation of CNS inflammation. Furthermore, microglia/macrophages remain IL-1β-negative during phagocytosis of apoptotic cells. The data demonstrate that phagocytic activity and pro-inflammatory microglial phenotype do not necessarily correlate.
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Affiliation(s)
- Martina M Hughes
- Trinity College Institute of Neuroscience and School of Biochemistry and Immunology, Trinity College Dublin, Dublin 2, Republic of Ireland
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Analysis of protein levels of 24 cytokines in scrapie agent-infected brain and glial cell cultures from mice differing in prion protein expression levels. J Virol 2009; 83:11244-53. [PMID: 19710140 DOI: 10.1128/jvi.01413-09] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Activation of microglia and astroglia is seen in many neurodegenerative diseases including prion diseases. Activated glial cells produce cytokines as a protective response against certain pathogens and as part of the host inflammatory response to brain damage. In addition, cytokines might also exacerbate tissue damage initiated by other processes. In the present work using multiplex assays to analyze protein levels of 24 cytokines in scrapie agent-infected C57BL/10 mouse brains, we observed elevation of CCL2, CCL5, CXCL1, CXCL10, granulocyte-macrophage colony-stimulating factor (GM-CSF), gamma interferon (IFN-gamma), interleukin 1alpha (IL-1alpha), IL-1beta, IL-6, and IL-12p40. Scrapie agent-infected wild-type mice and transgenic mice expressing anchorless prion protein (PrP) had similar cytokine responses in spite of extensive differences in neuropathology. Therefore, these responses may be primarily a reaction to brain damage induced by prion infection rather than specific inducers of a particular type of pathology. To study the roles of astroglia and microglia in these cytokine responses, primary glial cultures were exposed to scrapie agent-infected brain homogenates. Microglia produced only IL-12p40 and CXCL10, whereas astroglia produced these cytokines plus CCL2, CCL3, CCL5, CXCL1, G-CSF, IL-1beta, IL-6, IL-12p70, and IL-13. Glial cytokine responses from wild-type mice and transgenic mice expressing anchorless PrP differed only slightly, but glia from PrP-null mice produced only IL-12p40, indicating that PrP expression was required for scrapie agent induction of other cytokines detected. The difference in cytokine response between microglia and astroglia correlated with 20-fold-higher levels of PrP expression in astroglia versus microglia, suggesting that high-level PrP expression on astroglia might be important for induction of certain cytokines.
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Barry G, Breakwell L, Fragkoudis R, Attarzadeh-Yazdi G, Rodriguez-Andres J, Kohl A, Fazakerley JK. PKR acts early in infection to suppress Semliki Forest virus production and strongly enhances the type I interferon response. J Gen Virol 2009; 90:1382-1391. [PMID: 19264662 PMCID: PMC2885058 DOI: 10.1099/vir.0.007336-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Accepted: 02/03/2009] [Indexed: 12/20/2022] Open
Abstract
The double-stranded RNA-activated protein kinase (PKR) is a key regulator of protein translation, interferon (IFN) expression and cell survival. Upon infection of vertebrate cells in continuous culture, the alphavirus Semliki Forest virus (SFV) initiates apoptosis and IFN synthesis. To determine the effect of PKR on SFV infection, we studied the course of infection in wild-type (wt) mice, mice with a genetic deletion of PKR (PKR-/-) and mouse embryo fibroblasts (MEFs) derived from these mice. In MEFs, PKR delayed virus protein synthesis, production of infectious virus and caspase-3-activated cell death and reduced the yield of infectious virus by 90%. Small interfering RNA suppression of PKR levels in NIH-3T3 cells also reduced virus production and apoptosis. In MEFs, PKR was not required for initiation of IFN-beta gene transcription, but contributed strongly to the magnitude of this response. Levels of IFN-beta transcripts in PKR-/- MEFs at 8 h were 80% lower than those in wt MEFs and levels of functional IFN at 24 h were 95% lower. Following infection of wt and PKR-/- mice, SFV4 and SFV A7(74) were avirulent. PKR increased levels of serum IFN and the rate of clearance of infectious virus from the brain. In summary, in response to SFV, PKR exerts an early antiviral effect that delays virus protein production and release of infectious virus and, whilst PKR is not required for induction of apoptosis or activation of the type I IFN response, it strongly augments the type I IFN response and contributes to clearance of infectious virus from the mouse brain.
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Affiliation(s)
- Gerald Barry
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - Lucy Breakwell
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - Rennos Fragkoudis
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - Ghassem Attarzadeh-Yazdi
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - Julio Rodriguez-Andres
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - Alain Kohl
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - John K Fazakerley
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
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Fragkoudis R, Breakwell L, McKimmie C, Boyd A, Barry G, Kohl A, Merits A, Fazakerley JK. The type I interferon system protects mice from Semliki Forest virus by preventing widespread virus dissemination in extraneural tissues, but does not mediate the restricted replication of avirulent virus in central nervous system neurons. J Gen Virol 2008; 88:3373-3384. [PMID: 18024907 DOI: 10.1099/vir.0.83191-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Semliki Forest virus (SFV) infection of the mouse provides a powerful model to study the pathogenesis of virus encephalitis. SFV and other alphavirus-based vector systems are increasingly used in biotechnology and medicine. This study analysed the strong susceptibility of this virus to type I interferon (IFN) responses. Following intraperitoneal infection of adult mice, SFV strain A7(74) was efficiently (100 %) neuroinvasive. In contrast, SFV4 was poorly (21 %) neuroinvasive. Upon entry into the brain, both viruses activated type I IFN responses. As determined by quantitative RT-PCR, activation of the IFN-alpha gene was proportional to virus RNA load. An intact type I IFN system was required for protection against both strains of SFV. IFN strongly curtailed virus spread in many cell types and in many tissues. In mice with an intact type I IFN system, infected cells were rarely observed and tissue tropism was difficult to determine. In the absence of a functional type I IFN system, the tropism and the potential for rapid and widespread infection of this virus was revealed. Virus infection was readily observed in the myocardium, endocardium, exocrine pancreas, adipose tissue, smooth muscle cells and in the brain in meningeal cells, ependymal cells and oligodendrocytes. In the brains of mice with and without type I IFN responses, virus infection of neurons remained rare and focal, indicating that the previously described restricted replication of SFV A7(74) in neurons is not mediated by type I IFN responses.
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Affiliation(s)
- Rennos Fragkoudis
- Virology, Centre for Infectious Diseases, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh EH19 1QH, UK
| | - Lucy Breakwell
- Virology, Centre for Infectious Diseases, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh EH19 1QH, UK
| | - Clive McKimmie
- Virology, Centre for Infectious Diseases, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh EH19 1QH, UK
| | - Amanda Boyd
- Virology, Centre for Infectious Diseases, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh EH19 1QH, UK
| | - Gerald Barry
- Virology, Centre for Infectious Diseases, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh EH19 1QH, UK
| | - Alain Kohl
- Virology, Centre for Infectious Diseases, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh EH19 1QH, UK
| | - Andres Merits
- Institute of Technology, University of Tartu, Estonia
| | - John K Fazakerley
- Virology, Centre for Infectious Diseases, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh EH19 1QH, UK
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Bourteele S, Oesterle K, Weinzierl AO, Paxian S, Riemann M, Schmid RM, Planz O. Alteration of NF-kappaB activity leads to mitochondrial apoptosis after infection with pathological prion protein. Cell Microbiol 2007; 9:2202-17. [PMID: 17573907 PMCID: PMC2048569 DOI: 10.1111/j.1462-5822.2007.00950.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Nuclear factor kappa B (NF-kappaB) is a key regulator of the immune response, but in almost the same manner it is involved in induction of inflammation, proliferation and regulation of apoptosis. In the central nervous system activated NF-kappaB plays a neuroprotective role. While in some neurodegenerative disorders the role of NF-kappaB is well characterized, there is poor knowledge on the role of NF-kappaB in prion disease. We found binding but no transcriptional activity of the transcription factor in vitro. Characterizing the mechanism of cell death after infection with pathological prion protein increased caspase-9 and caspase-3 activity was detected and the lack of NF-kappaB activity resulted in the inability to activate target genes that usually play an important role in neuroprotection. Additionally, we investigated the role of NF-kappaB after prion infection of Nfkb1(-/-), Nfkb2(-/-) and Bcl3(-/-) mice and central nervous system-specific p65-deleted mice revealing an accelerated prion disease in NF-kappaB2- and Bcl-3-deficient mice, which is in line with a reduced neuroprotective activity in prion infection. Based on our findings, we propose a model whereby the alteration of NF-kappaB activity at the early stages of infection with pathological prion protein leads to neuronal cell death mediated by mitochondrial apoptosis.
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Affiliation(s)
- Soizic Bourteele
- Friedrich-Loeffler-Institut, Federal Research Institute for Animals Health, Institute of Immunology TübingenGermany
| | - Katja Oesterle
- Friedrich-Loeffler-Institut, Federal Research Institute for Animals Health, Institute of Immunology TübingenGermany
| | - Andreas O Weinzierl
- Department of Immunology, Institute for Cell Biology, Eberhard-Karls-University TübingenGermany
| | - Stephan Paxian
- Department of Internal Medicine II, Technical UniversityMunich, Germany
| | - Marc Riemann
- Department of Internal Medicine II, Technical UniversityMunich, Germany
| | - Roland M Schmid
- Department of Internal Medicine II, Technical UniversityMunich, Germany
| | - Oliver Planz
- Friedrich-Loeffler-Institut, Federal Research Institute for Animals Health, Institute of Immunology TübingenGermany
- For correspondence. E-mail ; Tel. (+49) 7071 967 254; Fax (+49) 7071 967 105
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Takenouchi T, Iwamaru Y, Imamura M, Kato N, Sugama S, Fujita M, Hashimoto M, Sato M, Okada H, Yokoyama T, Mohri S, Kitani H. Prion infection correlates with hypersensitivity of P2X7 nucleotide receptor in a mouse microglial cell line. FEBS Lett 2007; 581:3019-26. [PMID: 17544414 DOI: 10.1016/j.febslet.2007.05.057] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2007] [Revised: 05/11/2007] [Accepted: 05/18/2007] [Indexed: 11/23/2022]
Abstract
We recently established mouse microglial cells persistently infected with mouse-adapted scrapie ME7 (ScMG20/ME7) for in vitro study of prion pathogenesis. Here, we found that ScMG20/ME7 cells were hypersensitive to P2X7 receptor agonists, as demonstrated by sustained Ca(2+) influx, membrane pore formation, cell death, and interleukin-1beta release. P2X7 mRNA expression was upregulated in these cells, and also in scrapie-infected mice brains. Treatment with pentosan polysulfate eliminated the infectivity and disease-related forms of prion protein from ScMG20/ME7 cell cultures, however, hypersensitivity of P2X7 receptors remained. These results suggest that prion infections may strongly affect the P2X7 receptor system in mouse microglial cells.
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Affiliation(s)
- Takato Takenouchi
- Transgenic Animal Research Center, National Institute of Agrobiological Sciences, Ohwashi 1-2, Tsukuba, Ibaraki 305-8634, Japan
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Gene expression profiling on sheep brain reveals differential transcripts in scrapie-affected/not-affected animals. Brain Res 2007; 1142:217-22. [DOI: 10.1016/j.brainres.2007.01.033] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2006] [Revised: 01/09/2007] [Accepted: 01/10/2007] [Indexed: 01/21/2023]
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Stobart MJ, Parchaliuk D, Simon SLR, LeMaistre J, Lazar J, Rubenstein R, Knox JD. Differential expression of interferon responsive genes in rodent models of transmissible spongiform encephalopathy disease. Mol Neurodegener 2007; 2:5. [PMID: 17367538 PMCID: PMC1847514 DOI: 10.1186/1750-1326-2-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2006] [Accepted: 03/16/2007] [Indexed: 11/26/2022] Open
Abstract
Background The pathological hallmarks of transmissible spongiform encephalopathy (TSE) diseases are the deposition of a misfolded form of a host-encoded protein (PrPres), marked astrocytosis, microglial activation and spongiosis. The development of powerful gene based technologies has permitted increased levels of pro-inflammatory cytokines to be demonstrated. However, due to the use of assays of differing sensitivities and typically the analysis of a single model system it remained unclear whether this was a general feature of these diseases or to what extent different model systems and routes of infection influenced the relative levels of expression. Similarly, it was not clear whether the elevated levels of cytokines observed in the brain were accompanied by similar increases in other tissues that accumulate PrPres, such as the spleen. Results The level of expression of the three interferon responsive genes, Eif2ak2, 2'5'-OAS, and Mx2, was measured in the brains of Syrian hamsters infected with scrapie 263K, VM mice infected with bovine spongiform encephalopathy and C57BL/6 mice infected with the scrapie strain ME7. Glial fibrillary acidic expression confirmed the occurrence of astrocytosis in all models. When infected intracranially all three models showed a similar pattern of increased expression of the interferon responsive genes at the onset of clinical symptoms. At the terminal stage of the disease the level and pattern of expression of the three genes was mostly unchanged in the mouse models. In contrast, in hamsters infected by either the intracranial or intraperitoneal routes, both the level of expression and the expression of the three genes relative to one another was altered. Increased interferon responsive gene expression was not observed in a transgenic mouse model of Alzheimer's disease or the spleens of C57BL/6 mice infected with ME7. Concurrent increases in TNFα, TNFR1, Fas/ApoI receptor, and caspase 8 expression in ME7 infected C57BL/6 mice were observed. Conclusion The identification of increased interferon responsive gene expression in the brains of three rodent models of TSE disease at two different stages of disease progression suggest that this may be a general feature of the disease in rodents. In addition, it was determined that the increased interferon responsive gene expression was confined to the CNS and that the TSE model system and the route of infection influenced the pattern and extent of the increased expression. The concurrent increase in initiators of Eif2ak2 mediated apoptotic pathways in C57BL/6 mice infected with ME7 suggested one mechanism by which increased interferon responsive gene expression may enhance disease progression.
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Affiliation(s)
- Michael J Stobart
- Division of Host Genetics and Prion Diseases, Public Health Agency of Canada, Canadian Science Centre for Human and Animal Health, Winnipeg, MB R3E 3R2, Canada
- Department of Medical Microbiology and Infectious Diseases, Faculty of Medicine, University of Manitoba, Winnipeg, MB R3E 0W3, Canada
| | - Debra Parchaliuk
- Division of Host Genetics and Prion Diseases, Public Health Agency of Canada, Canadian Science Centre for Human and Animal Health, Winnipeg, MB R3E 3R2, Canada
| | - Sharon LR Simon
- Division of Host Genetics and Prion Diseases, Public Health Agency of Canada, Canadian Science Centre for Human and Animal Health, Winnipeg, MB R3E 3R2, Canada
| | - Jillian LeMaistre
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Manitoba, Winnipeg, MB R3E 0W3, Canada
| | - Jozef Lazar
- Department of Dermatology and Human Molecular Genetics Center, MCW, Milwaukee, WI 53226, USA
| | - Richard Rubenstein
- Department of Biochemistry, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA
| | - J David Knox
- Division of Host Genetics and Prion Diseases, Public Health Agency of Canada, Canadian Science Centre for Human and Animal Health, Winnipeg, MB R3E 3R2, Canada
- Department of Medical Microbiology and Infectious Diseases, Faculty of Medicine, University of Manitoba, Winnipeg, MB R3E 0W3, Canada
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Marcos-Carcavilla A, Calvo JH, González C, Moazami-Goudarzi K, Laurent P, Bertaud M, Hayes H, Beattie AE, Serrano C, Lyahyai J, Martín-Burriel I, Alves E, Zaragoza P, Badiola JJ, Serrano M. IL-1 family members as candidate genes modulating scrapie susceptibility in sheep: localization, partial characterization, and expression. Mamm Genome 2007; 18:53-63. [PMID: 17242860 DOI: 10.1007/s00335-006-0095-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2006] [Accepted: 10/30/2006] [Indexed: 01/08/2023]
Abstract
Scrapie (SC) is a transmissible spongiform encephalopathy (TSE) in sheep and goats. Susceptibility to this neurodegenerative disease is controlled mainly by point mutations at the PRNP locus. Other genes, apart from PRNP, have been reported to modulate resistance/susceptibility to SC. On the basis of several studies on Alzheimer's disease and different TSE models, and of requirement for correct homeostasis of cytokines in brain, IL1B and IL1RN were chosen as putative positional and functional candidate genes that might be involved in the polygenic variance mentioned above. In the present work, ovine IL1B and IL1RN genes were partially isolated and characterized, including promoter and other regulatory regions. In addition, several sequence polymorphisms were identified. Furthermore, their cytogenetic positions on sheep chromosomes were determined by FISH and confirmed by linkage analysis, localizing both genes in OAR3p22, a region previously described as carrying a QTL for SC incubation period in sheep. Finally, expression analyses were carried out in eight naturally SC-infected and five uninfected sheep with the same genotype for PRNP (ARQ/ARQ). This comparison was performed using real-time RT-PCR in samples of spleen and cerebellum. Results showed differences in the expression of both cytokines in cerebellum (p < 0.05) but not in spleen (p > 0.05).
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Affiliation(s)
- Ane Marcos-Carcavilla
- Departamento de Mejora Genética Animal, INIA, Ctra La Coruña Km 7.5, 28040, Madrid, Spain.
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25
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Perry VH, Cunningham C, Holmes C. Systemic infections and inflammation affect chronic neurodegeneration. Nat Rev Immunol 2007; 7:161-7. [PMID: 17220915 DOI: 10.1038/nri2015] [Citation(s) in RCA: 730] [Impact Index Per Article: 42.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
It is well known that systemic infections cause flare-ups of disease in individuals with asthma and rheumatoid arthritis, and that relapses in multiple sclerosis can often be associated with upper respiratory-tract infections. Here we review evidence to support our hypothesis that in chronic neurodegenerative diseases such as Alzheimer's disease, with an ongoing innate immune response in the brain, systemic infections and inflammation can cause acute exacerbations of symptoms and drive the progression of neurodegeneration.
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Affiliation(s)
- V Hugh Perry
- Southampton Neuroscience Group, School of Biological Sciences and School of Medicine, University of Southampton, Southampton SO16 7PX, UK.
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26
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Pasquali P, Nonno R, Mandara MT, Di Bari MA, Ricci G, Petrucci P, Capuccini S, Cartoni C, Macrì A, Agrimi U. Intracerebral administration of interleukin-12 (IL-12) and IL-18 modifies the course of mouse scrapie. BMC Vet Res 2006; 2:37. [PMID: 17192191 PMCID: PMC1769363 DOI: 10.1186/1746-6148-2-37] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2006] [Accepted: 12/27/2006] [Indexed: 11/10/2022] Open
Abstract
Background Prion diseases are characterised by a neurodegenerative pattern in which the function of immune system remains still elusive. In the present study, we evaluate if an exogenous treatment with Interleukin-12 (IL-12) and IL-18, able to activate microglia, is able to affect scrapie pathogenesis. Results Cytokines injected intracranially, induced a strong inflammatory response characterised by TNF-α production and microglia activation. Two groups of mice were injected intracerebrally with high dose of ME7 strain of scrapie containing IL-12 and IL-18 or sterile saline. Cytokines-treated mice showed a more pronounced accumulation of PrPSc in brain tissues at 90 days post-inoculation and a shorter mean survival times than untreated mice. Conclusion We can conclude that intracerebral administration of IL-12 and IL-18 can modulate scrapie pathogenesis possibly through a microglia-mediated pattern.
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Affiliation(s)
- Paolo Pasquali
- Department of Food Safety and Animal Health, Istituto Superiore di Sanità, viale Regina Elena 299, 00161, Rome, Italy
| | - Romolo Nonno
- Department of Food Safety and Animal Health, Istituto Superiore di Sanità, viale Regina Elena 299, 00161, Rome, Italy
| | - Maria Teresa Mandara
- Department of Biopathological Veterinary Science, Veterinary Medicine School, Università degli Studi di Perugia, Perugia, Italy
| | - Michele Angelo Di Bari
- Department of Food Safety and Animal Health, Istituto Superiore di Sanità, viale Regina Elena 299, 00161, Rome, Italy
| | - Giovanni Ricci
- Department of Biopathological Veterinary Science, Veterinary Medicine School, Università degli Studi di Perugia, Perugia, Italy
| | - Paola Petrucci
- Department of Food Safety and Animal Health, Istituto Superiore di Sanità, viale Regina Elena 299, 00161, Rome, Italy
| | - Silvia Capuccini
- Department of Biopathological Veterinary Science, Veterinary Medicine School, Università degli Studi di Perugia, Perugia, Italy
| | - Claudia Cartoni
- Department of Food Safety and Animal Health, Istituto Superiore di Sanità, viale Regina Elena 299, 00161, Rome, Italy
| | - Agostino Macrì
- Department of Food Safety and Animal Health, Istituto Superiore di Sanità, viale Regina Elena 299, 00161, Rome, Italy
| | - Umberto Agrimi
- Department of Food Safety and Animal Health, Istituto Superiore di Sanità, viale Regina Elena 299, 00161, Rome, Italy
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27
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Iwamaru Y, Takenouchi T, Ogihara K, Hoshino M, Takata M, Imamura M, Tagawa Y, Hayashi-Kato H, Ushiki-Kaku Y, Shimizu Y, Okada H, Shinagawa M, Kitani H, Yokoyama T. Microglial cell line established from prion protein-overexpressing mice is susceptible to various murine prion strains. J Virol 2006; 81:1524-7. [PMID: 17121794 PMCID: PMC1797525 DOI: 10.1128/jvi.01379-06] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Several lines of evidence suggest that microglia have important roles in the pathogenesis of prion diseases. Here, we establish a novel microglial cell line (MG20) from neonatal tga20 mice that overexpress murine prion protein. After exposure to Chandler scrapie, we observed the replication and accumulation of disease-associated forms of the prion protein in MG20 cells up to the 15th passage. Furthermore, MG20 cells were susceptible to ME7, Obihiro scrapie, and bovine spongiform encephalopathy agents. Thus, MG20 cell lines persistently infected with various murine prion strains provide a useful model for the study of the pathogenesis of prion diseases.
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Affiliation(s)
- Yoshifumi Iwamaru
- Research Center for Prion Diseases, National Institute of Animal Health, Kannondai 3-1-5, Tsukuba, Ibaraki 305-8602, Japan
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28
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McKimmie CS, Roy D, Forster T, Fazakerley JK. Innate immune response gene expression profiles of N9 microglia are pathogen-type specific. J Neuroimmunol 2006; 175:128-41. [PMID: 16697053 DOI: 10.1016/j.jneuroim.2006.03.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Revised: 03/15/2006] [Accepted: 03/20/2006] [Indexed: 12/25/2022]
Abstract
Glial cells, particularly microglia, are thought to play a pivotal role in initiating and guiding innate immune responses to CNS infections and in perpetuating inflammation and pathology in CNS diseases such as multiple sclerosis and Alzheimer's disease. We describe here the development and use of a new microarray designed to specifically profile transcript expression of innate immunity genes. Microarray analysis validated by quantitative PCR demonstrated an extensive range of pattern recognition receptor gene expression in resting N9 microglia, including Toll-like receptors, scavenger receptors and lectins. Stimulation with LPS or infection with virus modulated pattern recognition receptor, cytokine, chemokine and other innate immune transcripts in a distinct and stimulus-specific manner. This study demonstrates that a single glial cell phenotype has an innate capability to detect infection, determine its form and generate specific responses.
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Affiliation(s)
- Clive S McKimmie
- Virology, Centre for Infectious Diseases College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
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29
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McKimmie CS, Fazakerley JK. In response to pathogens, glial cells dynamically and differentially regulate Toll-like receptor gene expression. J Neuroimmunol 2005; 169:116-25. [PMID: 16146656 DOI: 10.1016/j.jneuroim.2005.08.006] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2005] [Accepted: 08/03/2005] [Indexed: 11/19/2022]
Abstract
The mechanisms that mediate innate immune recognition of CNS infections are unknown. This study provides a comparison of Toll-like receptor (TLR) gene expression in resting and virus infected CNS cells. N2a neuroblastoma cells expressed TLR 3 but demonstrated no change in TLR gene expression in response to either LPS or virus infection. N9 microglia and differentiated primary astrocytes expressed most TLR genes. TLR 2 expression was highest in N9 microglia and TLR 7 in astrocytes. In both glial cell types, LPS stimulation upregulated pro-inflammatory cytokines, TLR 2 and TLR 3 gene expression but down-regulated other TLR genes. RNA virus infection substantially increased levels of type-I interferon (IFN) and TLR 3 transcripts and to a lesser extent TLR 9 transcripts. Microglia and astrocytes thus have the ability to discriminate between pathogens and elicit an appropriate response.
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Affiliation(s)
- Clive S McKimmie
- Virology, Centre for Infectious Diseases, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
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30
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McKimmie CS, Johnson N, Fooks AR, Fazakerley JK. Viruses selectively upregulate Toll-like receptors in the central nervous system. Biochem Biophys Res Commun 2005; 336:925-33. [PMID: 16157304 DOI: 10.1016/j.bbrc.2005.08.209] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2005] [Accepted: 08/23/2005] [Indexed: 11/28/2022]
Abstract
The resting CNS is an immunospecialized environment, devoid of most immune processes, although substantial inflammatory responses can be initiated. The innate immune mechanisms mediating recognition of CNS infections are unknown. This study provides a comprehensive analysis of Toll-like receptor (TLR) gene expression in the resting and virus-infected murine CNS. TLR transcripts were expressed in the resting CNS with strikingly high expression of TLR 3. Extraneural infection with neuroinvasive Semliki Forest virus resulted in CNS infection followed by rapid selective upregulation of TLR gene expression. Upregulation was independent of T-cell responses. Upregulation of TLR gene expression was also observed following rabies virus infection. TLR upregulation was appropriate to the pathogen and proportional to the virus load. Upregulation of TLR 3 and 9 was dependent upon the type-I interferon response and may act to increase the threshold of sensitivity to detect virus infection in cells surrounding virally infected cells.
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Affiliation(s)
- Clive S McKimmie
- Centre for Infectious Diseases, College of Medicine and Veterinary Medicine, University of Edinburgh, UK
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31
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Dron M, Bailly Y, Beringue V, Haeberlé AM, Griffond B, Risold PY, Tovey MG, Laude H, Dandoy-Dron F. Scrg1 is induced in TSE and brain injuries, and associated with autophagy. Eur J Neurosci 2005; 22:133-46. [PMID: 16029203 DOI: 10.1111/j.1460-9568.2005.04172.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We have previously identified Scrg1, a gene with increased cerebral mRNA levels in transmissible spongiform encephalopathies (TSE) such as scrapie, bovine spongiform encephalopathy and Creutzfeldt-Jakob disease. In this study, Scrg1-immunoreactive cells, essentially neurons, were shown to be widely distributed throughout the brain of scrapie-infected mice, while only rare and weakly immunoreactive cells could be detected in the brain of non-infected normal mice. Induction of the protein was confirmed by Western blot analysis. At the ultrastructural level, Scrg1 protein was associated with dictyosomes of the Golgi apparatus and autophagic vacuoles in the central neurons of the scrapie-infected mice. These results suggested a role for Scrg1 in the pathological changes observed in TSE. We have generated transgenic mice specifically expressing Scrg1 in neurons. No significant differences in the time course of the disease were detected between transgenic and non-transgenic mice infected with scrapie prions. However, tight association of Scrg1 with autophagic vacuoles was again observed in brain neurons of infected transgenic mice. High levels of the protein were also detected in degenerating Purkinje cells of Ngsk Prnp 0/0 mice overexpressing the Prnd gene coding for doppel, a neurotoxic paralogue of the prion protein. Furthermore, induction of Scrg1 protein was observed in the brain of mice injured by canine distemper virus or gold thioglucose treatment. Taken together, our results indicate that Scrg1 is associated with neurodegenerative processes in TSE, but is not directly linked to dysregulation of prion protein.
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Affiliation(s)
- Michel Dron
- CNRS UPR-9045, Laboratoire d'Oncologie Virale, 7 rue Guy Môquet BP-8, 94801 Villejuif Cedex, France
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32
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Brown AR, Rebus S, McKimmie CS, Robertson K, Williams A, Fazakerley JK. Gene expression profiling of the preclinical scrapie-infected hippocampus. Biochem Biophys Res Commun 2005; 334:86-95. [PMID: 15992767 DOI: 10.1016/j.bbrc.2005.06.060] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2005] [Accepted: 06/10/2005] [Indexed: 11/15/2022]
Abstract
The molecular events that underlie prion disease neuropathology remain poorly defined. Within the hippocampus of the ME7/CV mouse scrapie model, profound CA1 neuronal loss occurs between 160 and 180 days post-infection (dpi). To elucidate the molecular events that may contribute to this neuronal loss, we have applied Affymetrix high-density oligonucleotide probe arrays to the study of ME7-infected hippocampal gene expression at 170 dpi. The study has identified 78 genes that are differentially expressed greater than 1.5-fold within the preclinical ME7-infected hippocampus prior to the profound late stage glial cell activation. The results indicate oxidative and endoplasmic reticulum (ER) stress, activated ER and mitochondrial apoptosis pathways, and activated cholesterol biosynthesis within the scrapie-infected hippocampus, and offer insight into the molecular events which underlie the neuropathology.
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Affiliation(s)
- Alan R Brown
- Centre for Infectious Diseases, University of Edinburgh, Edinburgh, Scotland, UK
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33
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Cunningham C, Wilcockson DC, Boche D, Perry VH. Comparison of inflammatory and acute-phase responses in the brain and peripheral organs of the ME7 model of prion disease. J Virol 2005; 79:5174-84. [PMID: 15795301 PMCID: PMC1069550 DOI: 10.1128/jvi.79.8.5174-5184.2005] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Chronic neurodegenerative diseases such as prion disease and Alzheimer's disease (AD) are reported to be associated with microglial activation and increased brain and serum cytokines and acute-phase proteins (APPs). Unlike AD, prion disease is also associated with a peripheral component in that the presumed causative agent, PrPSc, also accumulates in the spleen and other lymphoreticular organs. It is unclear whether the reported systemic acute-phase response represents a systemic inflammatory response to prion disease or merely reflects central nervous system (CNS) inflammation. For this study, we investigated whether intracerebrally initiated prion disease (ME7 model) provokes splenic, hepatic, or brain inflammatory and acute-phase responses. We detected no significant elevation of proinflammatory cytokines or activation of macrophages in the spleens of these animals, despite clear PrPSc deposition. Similarly, at 19 weeks we detected no significant elevation of transcripts for the APPs serum amyloid A, complement C3, pentraxin 3, and alpha2-antiplasmin in the liver, despite CNS neurodegeneration and splenic PrPSc deposition at this time. However, despite the low CNS expression levels of proinflammatory cytokines, there was robust expression of these APPs in degenerating brains. These findings suggest that PrPSc is not a stimulus for splenic macrophages and that neither peripheral PrPSc deposition nor CNS neurodegeneration is sufficient to produce a systemic acute-phase response. We also propose that serum cytokine and APP measurements are not useful during preclinical disease. Possible consequences of the clear chronic elevation of APPs in the CNS are discussed.
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Affiliation(s)
- Colm Cunningham
- CNS Inflammation Group, School of Biological Sciences, Bassett Crescent East, Southampton, Hampshire SO16 7PX, United Kingdom.
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34
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Unterberger U, Voigtländer T, Budka H. Pathogenesis of prion diseases. Acta Neuropathol 2005; 109:32-48. [PMID: 15645262 DOI: 10.1007/s00401-004-0953-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2004] [Accepted: 10/18/2004] [Indexed: 11/28/2022]
Abstract
Prion diseases are rare neurological disorders that may be of genetic or infectious origin, but most frequently occur sporadically in humans. Their outcome is invariably fatal. As the responsible pathogen, prions have been implicated. Prions are considered to be infectious particles that represent mainly, if not solely, an abnormal, protease-resistant isoform of a cellular protein, the prion protein or PrP(C). As in other neurodegenerative diseases, aggregates of misfolded protein conformers are deposited in the CNS of affected individuals. Pathogenesis of prion diseases comprises mainly two equally important, albeit essentially distinct, topics: first, the mode, spread, and amplification of infectivity in acquired disease, designated as peripheral pathogenesis. In this field, significant advances have implicated an essential role of lymphoid tissues for peripheral prion replication, before a likely neural spread to the CNS. The second is the central pathogenesis, dealing, in addition to spread and replication of prions within the CNS, with the mechanisms of nerve cell damage and death. Although important roles for microglial neurotoxicity, oxidative stress, and complement activation have been identified, we are far from complete understanding, and therapeutic applications in prion diseases still need to be developed.
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35
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Burwinkel M, Riemer C, Schwarz A, Schultz J, Neidhold S, Bamme T, Baier M. Role of cytokines and chemokines in prion infections of the central nervous system. Int J Dev Neurosci 2004; 22:497-505. [PMID: 15465279 DOI: 10.1016/j.ijdevneu.2004.07.017] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2004] [Accepted: 07/12/2004] [Indexed: 11/22/2022] Open
Abstract
Prion infections of the central nervous system (CNS) are characterised by a reactive gliosis and the subsequent degeneration of neuronal tissue. The activation of glial cells, which precedes neuronal death, is likely to be initially caused by the deposition of misfolded, proteinase K-resistant, isoforms (termed PrP(res)) of the prion protein (PrP) in the brain. Cytokines and chemokines released by PrP(res)-activated glia cells may contribute directly or indirectly to the disease development by enhancement and generalisation of the gliosis and via cytotoxicity for neurons. However, the actual role of prion-induced glia activation and subsequent cytokine/chemokine secretion in disease development is still far from clear. In the present work, we review our present knowledge concerning the functional biology of cytokines and chemokines in prion infections of the CNS.
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36
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Riemer C, Neidhold S, Burwinkel M, Schwarz A, Schultz J, Krätzschmar J, Mönning U, Baier M. Gene expression profiling of scrapie-infected brain tissue. Biochem Biophys Res Commun 2004; 323:556-64. [PMID: 15369787 DOI: 10.1016/j.bbrc.2004.08.124] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2004] [Indexed: 11/30/2022]
Abstract
The underlying pathomechanisms in prion infections of the central nervous system are still insufficiently understood. The identification of genes with altered expression patterns in the diseased brain may provide insight into the disease development on the molecular level, which ultimately leads to neuronal loss. To provide a detailed analysis of changes in the molecular level in prion disease pathology we used a large-scale gene array based approach, which covers more than 11,000 functionally characterised sequences and expressed sequence tags, for the analysis of gene expression profile alterations in the cortex, medulla, and pons of scrapie-infected mice. The study identified in total 114 genes with altered mRNA levels, the majority of which were previously not known to be affected by the disease. Overall the gene array data demonstrate the presence of a strong inflammatory reaction and stress response, and show similarities to gene expression patterns found in brains affected by Alzheimer's disease and aging, respectively.
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37
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Schultz J, Schwarz A, Neidhold S, Burwinkel M, Riemer C, Simon D, Kopf M, Otto M, Baier M. Role of interleukin-1 in prion disease-associated astrocyte activation. THE AMERICAN JOURNAL OF PATHOLOGY 2004; 165:671-8. [PMID: 15277240 PMCID: PMC1618583 DOI: 10.1016/s0002-9440(10)63331-7] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Prion-induced chronic neurodegeneration has a substantial inflammatory component, and the activation of glia cells may play an important role in disease development and progression. However, the functional contribution of cytokines to the development of the gliosis in vivo was never systematically studied. We report here that the expression of interleukin-1beta (IL-1beta), IL-1beta-converting enzyme, and IL-1 receptor type 1 (IL-1RI) is up-regulated in a murine scrapie model. The scrapie-induced gliosis in IL-1RI(-/-) mice was characterized by an attenuated activation of astrocytes in the asymptomatic stage of the disease and a reduced expression of CXCR3 ligands. Furthermore, the accumulation of the misfolded isoform of the prion protein PrP(Sc) was significantly delayed in the IL-1RI(-/-) mice. These observations indicate that IL-1 is a driver of the scrapie-associated astrocytosis and possibly the accompanying amyloid deposition. In addition, scrapie-infected IL-1RI-deficient (IL-1RI(-/-)) mice showed a delayed disease onset and significantly prolonged survival times suggesting that an anti-inflammatory therapeutical approach to suppress astrocyte activation and/or glial IL-1 expression may help to delay disease onset in established prion infections of the central nervous system.
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Affiliation(s)
- Julia Schultz
- Project "Neurodegenerative Diseases," Robert-Koch-Institute, Nordufer 20, 13353 Berlin, Germany
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38
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Brown AR, Webb J, Rebus S, Williams A, Fazakerley JK. Identification of up-regulated genes by array analysis in scrapie-infected mouse brains. Neuropathol Appl Neurobiol 2004; 30:555-67. [PMID: 15488032 DOI: 10.1111/j.1365-2990.2004.00565.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The major neuropathological features of the transmissible spongiform encephalopathies (TSEs) are well documented, however, the underlying molecular events are poorly defined. We have applied cDNA expression arrays and quantitative RT-PCR to the study of gene expression in the brain, and more specifically in the hippocampus, of the well-characterized ME7/CV mouse model of scrapie. The number of genes showing consistent, scrapie-associated changes in expression was limited, and was primarily restricted to glial-associated genes. Increased expression of genes encoding glial fibrillary acidic protein, vimentin, complement component 1q (alpha and beta polypeptides), cathepsin D, clusterin and cystatin C was evident in the hippocampus from 170 days after inoculation (dpi), with expression increasing thereafter to terminal disease (225-235 dpi). Elevation of gene expression preceded clinical disease by approximately 30 days, and coincided with a 20-day period in the ME7/CV model during which 50% of the CA1 hippocampal neurones are lost. Increased expression of cystatin C, an inhibitor of lysosomal cysteine proteases, is a novel finding in the context of TSE neuropathology and was confirmed by Western analysis and immunocytochemistry.
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Affiliation(s)
- A R Brown
- Centre for Infectious Diseases, University of Edinburgh, Edinburgh, UK
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